Fiber insulation, which is in widespread use in various industries such as the appliance industry, is effective insulation and is low cost, but poses the initial problem of handling the fibers during installation of the insulation on the devices to be insulated. Various methods have been used to contain the fibers and protect workers from the fibers, such as encapsulating the fiber materials in plastic film. Such methods have proven inadequate in many uses due to the limitations imposed by the thermal requirements of a particular installation. In addition, fiber insulation frequently loses its effectiveness in various applications due to impregnation with moisture or other contamination from condensation of vapors. Consequently, there is a need for effective devices and methods for encapsulating fiber insulation for installation and to protect the fiber insulation long-term from contamination to maintain the insulation effectiveness.